How to Avoid the Generation of Smoke in Laser Welding Processes？

Laser welding, as an efficient and precise welding technology, has been widely used in various industrial sectors. However, the generation of smoke during the laser welding process remains a common issue. Currently, it is difficult for the entire industry to achieve the goal of completely eliminating smoke production in laser welding. Similar to laser cutting, smoke exhaust systems are required in laser cutting machines. Compared to laser welding and traditional gas-shielded metal arc welding, tungsten inert gas (TIG) welding has its unique advantages. From the perspective of smoke, the production of smoke is more severe in TIG welding than in laser welding. Although TIG welding produces smoke at a slower speed, it is less visible. On the other hand, due to the small arc size in laser welding, the smoke is more visible. As laser welding machines are relatively new technologies introduced in the past two years, there are high expectations for laser technology, which is normal from a psychological standpoint.

Currently, there are two situations regarding the generation of smoke in laser welding. Firstly, smoke accumulation may occur on the workpiece, and secondly, smoke can be present in the air. Although visible smoke accumulation is not significant at the moment, it can still be found in the air. In the following discussion, we can explore the reasons for smoke generation during welding and provide potential solutions to reduce its occurrence.

Factors contributing to smoke generation:

1. The generation of smoke during welding is greatly influenced by the welding material. Different welding materials produce varying amounts of smoke. For instance, we have previously worked with aluminum alloy welding and found significant differences in smoke production among different aluminum alloys.
2. The presence of oil film protection or oxide layer on the workpiece’s surface can lead to the formation of oxides. These oxides easily evaporate at high temperatures, resulting in increased smoke generation during welding.
3. The type of welding wire used is also related to smoke emission. Currently, traditional welding wires are used, which are not specifically designed for the laser industry, making it more challenging to control smoke generation. It is recommended to use existing low-smoke welding wires.
4. Incomplete melting of the metal during welding can lead to the formation of metal particles. These particles are released into the air and solidify into tiny solid particles, resulting in smoke generation.
5. Smoke production during welding is related to various factors, such as welding speed, welding process, etc. For example, welding aluminum at low power may produce less smoke compared to high-power welding.
6.  When the lens is damaged, the welding effect is generally not good

Solutions:

1. Optimize welding parameters: By adjusting laser power, speed, focal length, and other parameters, it is possible to reduce the smoke and gas produced during the welding process.
2. Use appropriate shielding gas: Employing suitable shielding gases during welding can reduce the oxygen’s impact on the welding area, thereby minimizing smoke and gas generation.
3. It is necessary to ensure good ventilation conditions in the welding area, ensure air flow, and remove harmful gases and black smoke generated in time. For large equipment, purification equipment and smoke exhaust system should be used to filter and treat black smoke.
4. Provide necessary training and guidance to operators: Ensure that operators are properly trained to operate laser welding equipment, adjust welding parameters, and take appropriate safety measures to reduce the risk of smoke generation.

It is worth noting that the issue of smoke generation requires attention, and the mentioned approaches can be employed to reduce smoke production in laser welding. In practical applications, it is essential to consider various factors and adopt appropriate solutions based on specific circumstances to ensure the safety and efficiency of the laser welding process.At the same time, we also welcome more people to join in the discussion and research to find more effective solutions and promote the development of laser welding technology.